It has long been of interest to the energetic materials community to develop more environmentally friendly initiating compositions, since both of the most prevalent ingredients in use today, lead styphnate (LS) and lead azide (LA), release toxic lead compounds into the environment upon their decomposition. The challenge has been to identify non-toxic materials that have equivalent performance. Lead styphnate (LS) has been widely used in ordnance systems for many years. It is a reliable explosive material and its properties and manufacturing processes are well defined. Executive Order 12856 (1993) was issued to reduce or eliminate procurement of hazardous substances and chemicals by federal facilities. As a result, there have been a need to develop existing or new materials which would serve as a drop in replacement for LS and which incorporate no toxic or environmentally undesirable elements. Environmental health and safety regulations on lead containing materials are quite extensive and are likely to increase in severity in the future, along with compliance costs. The manufacture, use, demilitarization and disposal of LS (and ordnance containing them) are deeply impacted by these regulations, and lead-free alternatives to LS have been sought for many years.
U.S. Patent Application Publication No. 2009/0223401 to Fronabarger et al. discloses lead free primers wherein LS is replaced with KDNP (4,6-dinitro-7-hydroxybenzofuroxan, potassium salt). Disclosed therein is a three step process of making KDNP starting from m-bromoanisole, subjecting it to nitration, and reacting the resulting product with potassium azide (KN3), thereby producing KDNP.
There is a need for a less expensive, environmentally friendly alternative synthesis to make KDNP. There is a vast surplus of Explosive D that must be demilitarized. Explosive D is ammonium picrate. If it can be recycled, instead of burned or other demilitarized process, the impact on the environment is friendlier.